Photograph by Blane Perun

Coral Farm Metal Halide and Power Compact

Both of these lighting fixtures went in December of 2002 and were removed by February 2003. To my amazement I was still not able to achieve the striking color I once had with Zoanthus in my previous system under 175w Metal Halides. The strip light would have, however the distance required to keep a fluorescent off the water is about three inches, the intensity of light necessary for photosynthesis to occur under these bulbs requires closer proximity.

In this application I was constantly moving the fixture up and down which became a nuisance, so I opted to purchase a 20 K Metal halide fixture to run this tank. I elected to provide the large Polyp Stony tank with supplemental lighting from one of the new power quad pc bulbs on the market. The manufacturer claims to equal the output of a 175w bulb. While I did experience great coloration and growth under this fixture for three months I chose to sell it and replace it with a Metal Halide fixture.

The problem was mainly cost related. This fixture cost about two hundred

dollars, and the replacement on the bulb is around fifty / for 96 watts. As you can see from the photo to adequately cover the tank with light I would certainly need a second fixture. Economically, I would have about four hundred into the fixture and one hundred to replace the bulbs. I would need to keep both fixtures relatively close to the water, about six to eight inches. For a little over two hundred bucks I could put one Metal halide fixture above the tank, some eighteen inches high, light the whole tank and have a bulb replacement cost of around sixty bucks.

I decided to sell these fixtures and take a small loss rather than to push them for a year with minimal results and get far less than what I had paid. Below is an overhead shot from the ceiling in the farm, I had a ledge built around the perimeter to back light the room. I made it wide enough to hide ballast inside. Although this fixture appears very bright, and I have grown under them in the past some seven inches off the water, it was still not enough to bring the color out of the Zoanthus I once had. So as stated above this was recently sold off and replaced with two 250 watt Mental Halide pendants. In my old system I grew Zoanthus under two 175 watt MH pendants that were three inches from the water surface.

The corals to the right, as you can see one MH 250 watt pendant next to the 96 watt power quad (and yes it is on). The difference in output is pretty dramatic, after seeing this I certainly do not agree with the claims the manufacturer makes about matching the output of 175 watt fixture. From here I will populate the rest of the Farm with Metal Halide fixtures, and the wattages will vary between 175 watts to 400 watts. On my SPS system I plan to run two 400 watt lights and a 1000 watt 20k. I expect to be putting that system together and stocking it by late summer. At that point I will post the remaining information to this section outlining all of my lighting choices along with PAR and Lumens readings.

Blane Perun

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Whale in Ocean